The present invention relates to a multi-shouldered friction stir welding bobbin tool for friction stir welding and, more particularly, the present invention relates to using a multi-shouldered friction stir welding tool for simultaneous friction stir welding of a plurality of parallel joints between components having parallel portions.
The Friction Stir Welding (FSW) process is a solid-state based joining process, which makes it possible to weld a wide variety of materials alloys (aluminum, copper, stainless steel, etc.) to themselves and combinations (e.g. 6XXX/5XXX, 2XXX/7XXX, etc.) The joining is effected by a rotating FSW tool, which is forced into the joining area to heat it by friction and thus “plasticizes” the parts about it. Plasticized material flows around the axis of the rotating FSW tool, and the plasticized regions coalesce into sound metallurgical bonds.
In one embodiment, the present invention discloses a multi-shouldered friction stir welding tool comprising an integral shank-pin unit having a plurality of pin portions on the shank-pin unit, where the plurality of pin portions for plunging into a plurality of joints to perform a friction stir welding operation on the corresponding plurality of joints and, where a shank portion of the shank-pin unit is for attachment to an optional axial tension rod, a plurality of friction stir welding modules, each of the friction stir welding modules comprising a pair of shoulders that is connected to the shank-pin unit where each shoulder has a distal end and a proximal end, where the proximal end of each shoulder faces the pin portion of the shank-pin unit, whereby the shoulder and pin(s) rotate in unison, and a pair of split collars or a pair of nuts that is connected to the shank-pin unit and faces the distal end of each shoulder, where the plurality of friction stir welding modules are connected to each other whereby the modules rotate in unison to simultaneously make a plurality of parallel welds.